The prior art related to the flushing and filling automotive radiators and cooling systems is filled with diverse methods and apparatae for use in removing used antifreeze/coolant and replacing such with new antifreeze/coolant. Although numerous methods and apparatus have been devised to accomplish this process, such have had certain common and limiting features associated with the removal and introduction of antifreeze/coolant from and to the automotive cooling system. For example, "change-over" of a cooling system from used antifreeze/coolant to new antifreeze/coolant has generally involved the introduction of a flushing liquid or new antifreeze/coolant at the opening associated with the radiator cap while a second opening, typically an opening in the engine, is present in the automotive cooling system for the removal of the spent antifreeze/coolant. The second opening may be the drain plug at the bottom of the radiator or may be an opening formed by cutting or removing one of the hoses found in the automotive cooling system. Although the aforementioned general flush/fill process has been used for many years, this process is not without its problems. For example, when the second opening is the drain plug the contents of the cooling system actually flushed is generally only a portion of the total volume of the cooling system, since the thermostat in the automotive cooling system generally remains closed when in contact with the cool flushing water and, further, some of the antifreeze/coolant is trapped in the engine. Further, the new antifreeze/coolant is added to the cooling system and is necessarily admixed and contaminated with a significant amount of the old antifreeze/coolant.
A prior art search in the U.S. Patent and Trademark Office located the following patents relating to antifreeze/coolant change-over processes:
______________________________________ U.S. Pat. No. PATANTEE ______________________________________ 1,969,295 Davis 3,094,131 Williams 3,180,759 Falk 3,188,006 Falk 3,409,218 Moyer 4,083,399 Babish et al. 4,109,703 Babish et al. 4,127,160 Joffe 4,161,979 Stearns 4,176,708 4,209,063 Babish et al. 4,293,031 Babish et al. 4,790,882 Barnes 4,791,890 Miles et al. 4,793,403 4,899,807 Joffe 4,901,786 Vataru et al. ______________________________________
U.S. Pat. Nos. 4,083,399, 4,109,703, 4,127,160, 4,176,708, 4,209,063 and 4,293,031 disclose apparatuses for use in flushing an engine cooling system. These patents require the use of a complicated, console controlled, flushing apparatus which utilizes water pump, vehicle heater and radiator connections in order to provide a controlled pressurized flow of flushing liquid and entrained gas bubbles through the automotive cooling system. As in the '399 patent, the flushing systems in the '703, '063, and '031 patents pass the flow of flushing liquid through the radiator in first a reverse direction and then a forward direction. The remaining two patents ('160 and '708 patents) are concerned with the series of branch conduits and/or valving used in the flushing system.
U.S. Pat. Nos. 4,791,890, 4,793,403, 4,899,807 and 4,901,786 disclose engine coolant flushing and filtering systems wherein the coolant flushed from the vehicle radiator is filtered and then recirculated back into the system.
U.S. Pat. Nos. 1,969,295, 3,188,006 and 3,409,218 all disclose radiator flushing systems which utilize T-connections and valving similar to that disclosed in U.S. Pat. No. 4,790,882. The '295 patent utilizes a T-connection valve between cut portions of the lower supply hose between an engine and the radiator. Relative to the '295patent, the '006 and '218 patents disclose much more complicated flushing systems and neither of these patents sever the upper radiator hose in order to perform the flushing operation.
Another consideration involved in the change-over of used antifreeze/coolant from an automotive cooling system is the volume of used antifreeze/coolant and flushing liquids which result from the change-over process. Since most prior art processes involve draining the used antifreeze/coolant and the use of copious amounts of water as a flushing liquid, the net result of such prior art processes is the accumulation of a large volume of a mixture of the used antifreeze/coolant mixed with the water used as the flushing liquids. Since it is desirous to dispose of the resulting liquid in an environmentally responsible manner, preferably by recycle of the ethylene glycol of the used antifreeze/coolant, the generation of large volumes of liquid with high water content is undesirable. Unfortunately, the mixture liquids in such processes for the change-over of used antifreeze/coolant result in a liquid to be recycled containing up to about 90 weight percent water. Since a major cost in the recycle of the ethylene glycol in the used antifreeze/coolant is the removal of water, it is most advantageous to have a liquid for recycle which has as great a weight percent ethylene glycol as possible. This is to be contrasted with the used antifreeze/coolant which typically contains about 50 weight percent water.
The instant invention overcomes many of the problems associated with the prior art flush/fill process by providing a simple easy to use antifreeze/coolant change-over apparatus and process. A change-over apparatus and process is employed to facilitate removal of used antifreeze/coolant from a cooling system in conjunction with the introduction of new antifreeze/coolant.